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SPF record generator
Build an SPF record from the services that send mail for your domain, then count the DNS lookups it needs against SPF’s limit of 10.
Who sends mail for your domain?
TXT record at your domain
Rules that break SPF
- A domain may publish only one SPF record; two make receivers return an error (RFC 7208). Merge them into one.
- Every
include,a,mx,ptr,existsandredirectcosts a DNS lookup, nested includes count too, and more than 10 is a permanent error. The count above follows each include. - Gmail and Yahoo require SPF or DKIM from every sender, and both plus DMARC from bulk senders (sender requirements).